#include <map>
#include <set>
#include <list>
#include <cmath>
#include <ctime>
#include <deque>
#include <queue>
#include <stack>
#include <string>
#include <bitset>
#include <cstdio>
#include <limits>
#include <vector>
#include <climits>
#include <cstring>
#include <cstdlib>
#include <fstream>
#include <numeric>
#include <sstream>
#include <iostream>
#include <algorithm>
#include <unordered_map>

using namespace std;


int main(){
    int n;
    cin >> n;
    int xarray[n];
    int yarray[n];
    for(int a0 = 0; a0 < n; a0++){
        int x;
        int y;
        cin >> x >> y;
        xarray[a0] = x;
        yarray[a0] = y;
        }
    
    // Go through all x's
    bool samex = true;
    for(int i = 0; i < n - 1; i++)
        {
        if(xarray[i] != xarray[i+1])
            {samex = false;}
        }
    
    if(samex == true)
        {
        cout << "YES";
        return 0;
        }
    
    
    
    // Go through all y's
    bool samey = true;
     for(int i = 0; i < n - 1; i++)
        {
        if(yarray[i] != yarray[i+1])
            {samey = false;}
        }
    if(samey == true)
        {
        cout << "YES";
        return 0;
        }
    
    cout << "NO";
    return 0;
}